An amusement park ride consists of a large vertical cylinder that spins about its axis fast enough that any person inside is held up against the wall even when the floor is removed. The coefficient of static friction between the person and the wall is u, = 0.3 and the radius of the drum is R = 2m. (a) Find wmin. the minimum angular speed at which the drum should rotate such that the person is held up even if the floor is removed. (hint: when the floor is removed, the person is held up by the static frictional force). (b) Find the linear speed of the person when the drum is rotating at the minimum angular speed you found in (a) (c) Suppose that the drum started from rest and reached the speed you found in (a) in 120 seconds. During this time the drum had constant angular acceleration. Find the number of rotations made by the person within this time.

An amusement park ride consists of a large vertical cylinder that spins about its axis fast enough that any person inside is held up against the wall even when the floor is removed. The coefficient of static friction between the person and the wall is u, = 0.3 and the radius of the drum is R = 2m. (a) Find wmin. the minimum angular speed at which the drum should rotate such that the person is held up even if the floor is removed. (hint: when the floor is removed, the person is held up by the static frictional force). (b) Find the linear speed of the person when the drum is rotating at the minimum angular speed you found in (a) (c) Suppose that the drum started from rest and reached the speed you found in (a) in 120 seconds. During this time the drum had constant angular acceleration. Find the number of rotations made by the person within this time.

International Edition---engineering Mechanics: Statics, 4th Edition

4th Edition

ISBN:9781305501607

Author:Andrew Pytel And Jaan Kiusalaas

Publisher:Andrew Pytel And Jaan Kiusalaas

Chapter7: Dry Friction

Section: Chapter Questions

Problem 7.24P: A uniform plank is supported by a fixed support at A and a drum at B that rotates clockwise. The...

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